Mechanical movement.



No. 727,310. PATENTBD MAY 5, 1903.

. T. B. DOOLEY. MECHANICAL MOVEMENT.

APPLICATION FILED JUNE 17, 1902.

N0 MODEL. 2 SHBETSSH EET 1.

No. 727,310 'PATENTED MAY 5, 190a.

a T. B. 'DOOLEY'.

MECHANICAL MOVEMENT.

APPLICATION FILED JUNE 17 1902.

N0 MODEL. 2 SHEETS-SHEET 2.

UNTTEE STATES.

Patented May 5, 1903.

PATENT ()FFICE.

THOMAS E. DooLEY, OF MALDEN, MASSACHUSETTS, AsSrcNoR To JOSEPH MIDDLEBY, JE., or MALDEN, MASSACHUSETTS.

MECHANICAL MOVEMENT.

SPECIFICATION forming part of Letters Patent No. 727,310, dated May 5,1903.

Application filed June 1'7, 1902. Serial No. 112,022. (No model.)

To all whom it may concern:

Be it known that I, THOMAS E. DOOLEY, a citizen of the United States, and a resident of Malden, in the county of Middlesex and 5 State of Massachusetts,have invented certain new and useful Improvements ,in Mechanical Movements, of which the following is a specification.

My invention relates to mechanical movements of that class in which the continuous rotation of one part produces an intermittent rotation of another part, of which mechanisms intermittent gears, so called, are a familiar example. Where the power required is to be transmitted by such a mechanismis considerable or where the velocity is high, a

sudden strain is put upon the driven member every time the latter is started,- which strain not only causes an objectionable shock or jar,

but also when the driving member is a mutilated gear is very liable to strip or break off the first engaging tooth of said gear.

Myinvention isintended to provide a mechanism of the character referred to which will operate without causing the objectionable strain above described, and to this end I employ, in combination with driving and driven gears or equivalent parts, a device which at the instant when the driven gear is to be 0 started operates to transmit a starting pressure or impulse from the driving to the driven gearindependently of the teeth of said gears,

the arrangement thus operating, in effect, as

a substitute for the first tooth of the driving- 5 gear. By these means undue strain on the first engaging tooth is prevented, and my preferred construction is such that the transmitting device also operates without shock or jar, as will be hereinafter set forth.

The mechanism herein shown and described is particularly designed and adapted for use in jobbing printing-presses for producing the necessary dwell of the platen while the sheets to be printed are being fed to the machine; 5 but it will be evident that my invention is not limited to such use.

My invention in its preferred form is illustrated in the accompanying drawings, in which Figure 1 is a side elevation of the mechanism in that position in which the driven memher is about to be started. Fig. 2 is an edge view of the parts shown in Fig. 1 looking from ,the right of said Fig. l.- Fig.3 is a view similar to Fig. 1, but showing the parts in a different position.

My invention is illustrated in the drawings as applied to cooperating gears 2 and 3, of which'the former is the driving-gear and the latter is the driven gear. It will be understood that these gears are suitably connected to the apparatus with which my device is to be used, being shown as secured to shafts 4 and 5, respectively. The driving-gear 2 is a mutilated gear, having no teeth on such a portion of its periphery, as shown at 6, as will provide for the desired dwell in the rotation of the driven gear. As it is usually desirable to positively lock the driven member against rotation during this dwell, l have shown the gear 3 as provided with means commonly employed for this purpose, consisting of a stop portion 7, which has its outer edge curved to make a sliding fit with the curved portion 6 on the gear 2, the gear 3 being thereby held immovable while the portion 6'is moving past the portion 7. This means for locking the driven gear during the desired dwell forms no part of my invention and may be replaced by any other suitable device for stopping or looking said gear or the parts 'driven thereby.

On a suitably-supported fixed stud 8 is journaledan arm 9, which is normally held against a stop 10 by means of a spring 11. A pin 12 is secured to the gear 3, and one end ofthe arm 9 is provided with a notch 13, adapted to receive said pin, the position of the studs being such that as the gear 3 1'0- tates the pin 12 will enter the notch 13 shortly before the dwell in the rotation of this gear occurs and will thereupon engage the arm 9 and turn it from its normal position, which is that shown in Fig. 3, into the position shown in Fig. 1, in which position the arm 9 will evidently remain stationary during the aforesaid dwell. The arm 9 is also provided, preferably at its opposite end, with a flange 14, which projects inwardly or toward the gear 2 and is so located that when no the arm 9 is in the position shown in Fig. 1 said flange will lie in the path of a pin 15, se

.parts driven thereby.

cured to the gear 2. The parts are so proportioned and located that just as the end of the aforesaid dwell is reached and the first tooth 16 of the gear 2 is about to engage the gear 3 and start the latter the pin 15 Will come in contact with the flange 14:, whereupon while the gear 2 is turning through an angle measured by the distance between the centersof two adjacent teeth the pin 15, operating on the flange 14, will turn the arm 9 through such an angle that its notched end, which is in engagement with the pin 12, will operate to move the circumference of the gear 3 through the distance between the centers of two of its teeth. The result of this operation will be that the gear 3 will be started at the proper velocity by a pressure or impulse transmitted to it through the arm 9 instead of through the tooth 16, so that all strain will be taken off the said tooth, and, in fact, the tooth itself may be wholly omitted. After the gear 3 has thus been started and the inertia of the parts driven thereby has been overcome the teeth of the gears mesh, the pin 12 moves out of the notch 13, and past the end of the arm 9, and the pin 15 passes the inner end of the flange 14,whereu pon the arm 9 is drawn back against the stop 10 and remains in the position shown in Fig. 3 until it is again engaged and operated by the pin 12, as above described. It will be evident that the starting pressure may be given a longer or a shorter duration than that above described, if desired, by suitably shaping and proportioning the notch 13 and the flange 14.

It will be noticed that in the arrangement shown in the drawings the flange 14 is located at an acute angle with respect to the path in which the pin 15 travels during its engagement with said flange and moves laterally out of said path, the result being that the arm 9 is operated .without imparting any substantial shock or jar to the gear 3 andthe It will also be seen that my invention provides a very simple construction which can readily be attached to any ordinary pair of intermittent gears by merely supplying each gear with a suitable termittent gears, and hence I do not consider my invention to be limited to the specific construction herein shown and described.

I claim as my invention 1. The combination with intermittent gears each provided with a projecting pin, of an arm pivoted to a fixed support and arranged to be engaged by the pin carried by the driving-gear and thereupon to transmit a starting impulse to the pin carried by the driven gear.

2. The combination with intermittentgears, each provided with a projecting pin, of an arm pivoted to a fixed support and provided with a notched end normally located in the path of the pin carried by the driven gear, and with a flange located in the path of the pin carried by the driving-gear, and means for restoring said arm to its normal position, substantially as described.

3. The combination withintermittentgears, each provided with a projecting pin, of an arm pivoted to a fixed supportand provided with a notched end normally located in the path of the pin carried by the driven gear, and also provided with a flange located in the path of the pin carried by the driving-gear and forming an acute angle with said path, and means for restoring said arm to its normal position, substantially as described.

4. The combination with intermittent gears, of a pivoted arm 9, a stop 10 and a spring 11, said arm being provided with a notch 13 and a flange 14, and pins 12 and 15 secured to said gears respectively, substantially as described.

In testimony whereof I have hereunto subscribed my name this 12th day of June, 1902.

THOMAS B. DOOLEY.

Witnesses:

E. D. CHADWICK, JOSEPH T. BRENNAN. 

